Реферат: Three Gorges Dam Essay Research Paper 10

The Three Gorge reservoir is currently designed to hold 20 billion cubic meters at the flood level. But this capacity is only equivalent to 4% of the total run off water in the region. “It is obvious from common sense that this capacity could not hold back flood waters enough to reduce significantly the flood risk at the lower reaches.” (Dr. Yegang Wu, senior scientist from Florida Water Management District)

Another problem is the fact that the Yangzi carries a large amount of silt. This silt can be carried all the way to the dam and a big ‘mud pond’ could result. There is no such technology available to divert or collect the silt at the dam. From an ecological point of view, the dam will be clogged by the large silt deposits, in the Yangzi, and will also trap much of the pollutants that normally would be washed out to the ocean. Along the Yangzi, about 80 percent of the cities do not have sewage systems, and it is cheaper to dump the waste in the river instead of a sewage treatment plant.

4.4 Loss of identity

Burial grounds in both Wushan and Fengjie counties, Sichuan are known to have been dynamited to make way for scientific excavations in advance of the dam project. One thousand tombs dating between the Han and Ming periods (206 BC to AD 1644) were also blasted away.

The problem lies with lack of funding. The initial budget (US$250 million) for excavation and preservation was reduced to US$37.5 million. Only a small amount of this sum has been distributed to local authorities because government officials have been unable to decide which agency should administer the funds.

4.5 Cost of dam

The Three Gorges dam will be the most expensive single construction project in history. The Chinese leaders are so determined to build the dam, that they haven’t considered whether it is economically viable.

In 1992 the official cost of the dam was set to US$11 billion. Estimates now exceed US$75 billion. This could slow down China’s recent economic boom.

5.0 Alternatives

The dam project is heavily funded by foreign export agencies. If people in foreign countries were to stop foreign investors and government organisations which support the project, the Chinese officials would have no choice but to reconsider their plans. But since it is not in the foreign investors’ best interest monetarily, they have kept supporting the Chinese government.

Hydrological experts have argued that effective flood management includes dyking, flood proofing, flood warning systems, diversion areas, and development restrictions in floodplain and designated diversion areas and that dams are not always the answer.

5.1 Many smaller dams

The Chinese officials’ mentality is that the “biggest structure” is the best structure, but what they must realize is that it does not mean the best structure. That Chinese hydropower could be produced on a number of tributaries that flow into the Yangzi. This procedure has been proven by scientific examples that prove that separate dams will produce more power and last longer then one main dam. Sedimentation of separate dams would be less and these dams would be able to preserve China’s cultural history.

The greater amount of smaller dams would cause less soil erosion and more power for a much lower cost. It would be able to compete with China’s booming industrial sectors and preserve the aquatic life. The construction of these smaller dams could also mean that it would lesson the amount of people to be resettled, and would save the Chinese government billions of dollars. However, the smaller dams would not allow large transportation of cargo down the river.

5.2 Cogeneration plants

Based on a recent study by United States and Chinese energy research institutes, which compared conventional sources with advanced generating technologies, cleaner alternatives, such as smaller gas turbines or cogeneration plants were found to be more economical for power generation than big hydro dams. Combined cycle gas turbines could provide power with lower capital costs and greater reliability than the Three Gorges dam and with far fewer emissions than conventional coal plants.

Combined cycle plants are commonly fuelled with natural gas, which burns more thoroughly than solid or liquid fuels. And unlike coal, it contains no heavy metals or sulfur emissions that cause acid rain.

Combined cycle plants can be installed and generating power reliably within nine months to two or three years for larger units. Three Gorges dam is scheduled to take 17 years.

In addition energy specialists argue, that switching from coal to gas, and using new technology of combined cycle gas turbines or cogeneration, would create greater environmental benefits than the Three Gorges dam by a 60% reduction of carbon dioxide emissions. Whereas the Three Gorges dam would reduce carbon dioxide emissions by only 5%.

6.0 Conclusions

The viability of the dam has to be reconsidered.

The economical and environmental cost of the dam outweighs its benefits.

The dam is not a feasible solution to China’s energy problems.

The Three Gorges dam may not prevent flooding.

There are other cost effective, time effective, more environmentally friendly solutions available, such as building cogeneration plants.

Human rights have been violated to build this dam.

7.0 Personal opinion

I believe that the Three Gorges dam project is not being built to prevent flooding or create needed energy, because there are cheaper, quicker ways of achieving such a goal as I have suggested in the alternatives to the Three Gorges dam. I have a feeling that the Chinese government simply wants to use the dam as a symbol of their strength and newly found wealth. Also by building the dam, they will be able to ‘prove’ that their communist system is working, since Chinese communist leaders in the past have suggested building the dam.

Having lived for a total of about one year in various Asian countries, including China, I have a greater understanding of the Asian culture and way of thinking. I have come to the conclusion that the Asian countries in general have no respect for their environment whatsoever. This could be due to the fact that bribery between companies and government is rampant throughout Asia. I was appalled at the amount of pollution in the rivers in Taiwan. And rubbish dumping at famous historical sites in China.

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